For (4) you need to know that the area of a rectangle is the product of the length and width.
For (5) and (6) the product of two positive or two negative numbers is positive while the product of one positive and one negative number is negative.
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can any1 plz help me with number 4 and 6 ooh and 5 if u feel generous..
number 6s text isn't clear..
Using the graphs explain where the product of the two straight lines will be zero, positive and negative.
Multiply these two expressions to find the expression for the area.
For a product of two values to be positive, what must be the signs on the two numbers? For a product of two values to be negative, what must be true of the two signs? For a product of two values to be zero, what must at least one of the values be?
Use this information to figure out the intervals of sign on the graph, keeping in mind that "on the x-axis" means that y is zero, "above the x-axis" means y is positive, and "below the x-axis" means y is negative.
Hope that helps!